осуществите следующие превращения C3H8-->C3H7Br-->C4H10-->C4H8-->CO2

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разбор слова по составу - кузнец

Open she brackets and put the verbs into the proper tense form.
Long ago there lived an old woman in England. She 1_________ (have) a son who 2_________ (be) a sailor. He 3________ (go) to different countries and always 4________ (bring) presents for his old mother. Once he 5________ (go) to China and 6________ (bring) some tea from that country. At that time tea 7________ (be) very expensive and only rich people 8________ (can) buy and drink it. So the old woman was very happy to have it. But she 9________ (not know) what to do with it. She 10________ (think) it 11________ (be) a vegetable. She 12________ (invite) her friends to taste it with her. At last the day of the party 13________ (come). The woman 14_________ (put) a big dish with tea-leaves on the table. The guests 15________ (begin) to eat them with salt and pepper and they 16________ (not like) it. Some time later the sailor 17________ (come) into the room. "What 18________you_______ (do)? " he asked. «Where 19_________ (be) the water in which you have boiled the leaves? » "I 20_______ (throw) it away, » his mother answered.

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Автомобиль,движущийся со скоростью 72 км/ч, осуществляет аварийное торможение с ускорением 5 м/с^2. Чему равна скорость автомобиля на половине тормозного пути?